Electric switch



April 9, 1940.

AP. HuTT 2,196,865

ELECTRIC SWITCH Filed March 23, 1939 philip HU t,

-lis Attohngy.

Patented Apr. 9, 1940 PATENT OFFICE ELECTRIC SWITCH Philip Hutt, New Haven, Conn., assignor to General Electric Company, a corporation of New York Application March 23,

9 Claims.

This invention relates to electric switches of the type -having liquid contact circuit controllers for controlling the flow oi current through the switch. The object of the invention is the provision of an improved construction and arrangement in switches of this type which may be easily assembled and manufactured at low cost.

In the accompanying drawing Fig l illustrates 1 l one use to which the switch may be put; Fig. 2

is a Sectional view through the Switch; Fig. 3 is a sectional view along the lines 3 3 of Fig. 2; Fig. 4 is a view of the interior of the switch; Fig. 5 is a Sectional view along the line 5-5 of Fig. 4; and Fig. 6 is a view showing the construction and operation of the liquid contact circuit controller.

Referring to the drawing, and more particularly to Fig. 6, the invention has been illustrated using a liquid contact circuit controller C having a pair of cup-shaped metal terminals I which are Separated by an insulating diaphragm 2 of a refractory material, Such as a ceramic. material, 'Ihe edges of the terminals are sealed by a bead 3 ofglass which also seals the junctions between the diaphragm and the terminals. Within the space enclosed by the terminals is a suitable quantity of mercury 4 which`forms the conducting medium between the terminals. In the man' ufacture of the circuit closer the space enclosed by the terminals is evacuated and filled with hydrogen at a pressure of one or more atmospheres which increases the current-interrupting capacity of the circuit closer. As shown by the full lines in Fig. 6, the diaphragm 2 is provided with an opening 5 which is submerged in themercury when' the circuit controller is in the current-conducting position. When the circuit controller is in the current-interrupting position, shown in dotted lines in Fig. 6. the opening 5 is above the mercury and the circuit between the terminals is therefore broken by the insulating diaphragm 2. Due to the construction of the circuit controller the interruption of the circuit between the terminals takes place in the mercury as the circuit closer is turned so that the opening 5 in the diaphragm approaches the dotted line position. This construction is illustrative of liq.- uid contact circuit controllers which are suitable for use in a switch embodying this invention.

The switch in Figs. l to 5, incusive, has a frame comprising spaced longitudinal bars I0 supported at one end by a base Il ci insulating material and at the other end by a plate i2. The bars III and the plate I2 may be formed of sheet metal. Supporting elements for the liquid contact circuit controller are mounted on each side o the base 1939, serial Nn. y263,695

(Cl. zoo- 54) II and are formed of metal straps having blades I3 gripping the terminals of the circuit controller and bent ends I 4 providing terminals for receiving the terminal screws I5. Each of the blades I3 is provided with a substantially circular pro- 5 jection I6 which engages a corresponding cup shaped terminal of the circuit closer. This forms a bearing structure for rotatably mounting the circuit closer. The supporting blades I3 are insulatedv from the bars I0 by plates I1 formed, 10 for example, of sheet ber insulating material and the bars l0, plates Il and blades I3 are held in assembled relationship on the base II by a rivet I8, or other suitable fastening means. In order to insulate the blades I3 one from the other, the 15 rivet IB is covered with a sleeve I9 of insulating material. The terminal Screws are separated from one another by a barrier 20 projecting integrally from the base II.

Operating .neans for the circuit controller in- 20 cludes fa pinl 2| which is slidably mouned in the plate I2 and in a cross-bar 22 spanning the longitudinal bars I0 between the base II and plate I2.

At one end the pin is provided with .t head 23 which cooperates with a coiled spring 24 sur- 25 rounding the pin and which is compressed between the head and the cross-bar 22. A cap 25 encloses the headed end of the pin and conceals the spring 24. At the other end, the pin is of reduced cross-section, as shown at 26, and car- 30 ries two disks 21 of insulating material disposed between a washer 28 and the peened over end 29 of the pin. An operating clement, for example a spring 30, is attached to the pin 2l by beingl formed with an offset portion 3| clamped between 35 the insulating disks 21. The spring is substantially U-shaped and is provided with arms 32 and 33 extending toward the liquid circuit controller. The arm 32 is provided with a bent end 34 extending through anopening in a disk 35' mounted on 40 one of the terminal members of the circuit controller; disk 35 is provided with a central opening to form, in effect, an annulus so that it may be slipped on to one of the terminals oi the circuit controller for fricticnal engagement therewith.

The disk 35 may be made of insulating material, such as sheet fiber, but this is not necessary as the spring is electrically connected to the circuit controller as will appear hereinafter. By this arrangement longitudinal movement of the pin 2I and spring -30 produces rotational movement of the disr 35.

In order to provide for rotation of 'the circuit way 31 formed in the terminal of the circuit closer. This means that longitudinal movement of the pin 2| is translated into rotative movement of the liquid contact circuit closer which rotates about the bearings I6. Rotation of the circuit controller moves the bent end 34 of the spring in an arcuate path parallel to the outer periphery of the circuit controller and, since the other end of the spring is fixed to the pin 2| the arm 32 is made iiexible to take care of the lateral movement of the bent end relative to the pin 2|. This means that the structure translating reciprocatory movement of the pin 2| into rotative movement of the circuit controller is greatly simpliiied inasmuch as it is unnecessary to provide a pivot bearing for the arm 32 at its point of connection with the pin 2| such as would be required if the arm 32 were a rigid member. Flexure of the spring arm 32 produces a slight lateral component of force on the circuit controller in a downward direction, in the showing of Fig. 2. This force is overcome by extending the other spring arm 33 into engagement with the other side of the circuit closer where the end of the arm is iiared outwardly, as shown at 38, and rests upon the terminal member of the circuit closer. This means that upon longitudinal movement of the pin 2| both the spring arms 32 and 33 are flexed outwardly, or spread apart, the arm 32 rotating the circuit controller and the arm 33 counterbalancing the component of force induced by the arm 32 with the flared end 38 sliding over the terminal of the circuit controller.

The switch mechanism thus far described may be placed as a unit within a protective casing or shell 39 having a lining sleeve 40, of insulating material. At one end the casing is provided with an opening 4| for receiving the conductors to be connected to the switch terminals and at the other end the casing is flared outwardly, as shown at 42, and closed by a face plate 43 secured in position by screws 44. The base of the switch mechanism rests upon the innerwall of the insulating shell while a portion of the mounting plate I2 is clamped between the end of the casing and the face plate 43, as shown at 45. In this manner the switch mechanism is mounted securely within the casing with the pin 2| and cap 25 extending outwardly beyond the coniines of the casing through an opening 46 formed in the face plate.

The opening 5 in the ceramic barrier and the keyway 31 in the terminal of the circuit controller may be so arranged that the switch may be operated in either a normally off or on position. In the form of the invention illustrated by Fig. 2, the switch is in on position when the plunger pin 2| is in extended position. Manifestly, the keyway may be so placed on the circuit controller that the switch is in off position when the plunger is extended.

One of the uses to which the switch may be put is as a door switch. This use is illustrated by Fig. l. The switch is mounted on the jamb 4l by means of the face plate so that as the door 48 is opened and closed it reciprocates the pin 2| causing rotation of the circuit controller to control the electrical circuit through the switch. The spring 24 forces the pin to extended position when the latter is released by the door.

The flexible spring arms 32 and 33 provide a simple and eiective means for interconnecting the rotatable circuit closer and reciprocatory pin. The arms may be made of light spring Wire and give a very smooth operation of the circuit controller. By counter-balancing the lateral component of force induced by the slight flexure of the arm 32, the arm 33 maintains the circuit closer seated securely upon the bearing surfaces I6 and reduces wear at those points. While the spring arms 32 and 33 have been shown and described as forming integral parts of the spring 30, it should be manifest that the arms may be formed of separate elements. In some cases, the counterbalancing spring arm 33 may be omitted although this arm has been shown and described as a preferred form of the invention. inasmuch as the ilared end of the arm 33 bears against one terminal of the circuit controller, this arm is in electrical connection with one part ot the circuit controller so that it is desirable to insulate the arm from the switch-operating mechanism, particularly the operating pin 2 I. This is accomplished by the insulating disks 21 which support the spring 30 and the arms 32 and 33 upon the operating pin and at the same time insulate the latter from the spring arms. The portion of the spring gripped by thev disks is spaced from the central reduced portion 26 of the pin, by being curved around the pin, as shown by Fis. 3.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In an electric switch, a liquid contact circuit controller operable by rotation about its axis, a disk keyed to said circuit controller, an operating pin slidably mounted for reciprocatory movement, and a flexible spring arm interconnecting said operating pin and disk for translating reciprocating movement of said pin into rotation of said circuit controller.

2. In an electric switch, a liquid contact circuit controller operable by rotation about its axis, a member keyed to said circuit controller, an operating pin slidably mounted for reciprocatory movement, and a flexible spring member pivotally connected at one end to said ilrst-mentioned member and being fixed at the other end to said pin for translating reciprocating movement of said operating pin into rotation of said circuit controller.

3. In an electric switch, a liquid contact circuit controller operable by rotation about its axis, an element slidably mounted for reciprocatory movement, and a flexible spring member pivotally connected at one end to said circuit control- 1er and being fixed at the other end to said element for translating reciprocating movement of said element into rotation of said circuit controller.

4. In an electric switch, a liquid contact circuit controller operable by rotation about its axis, an operating element slidably mounted for reciprocatory movement, a ilexible spring arm, one end of said spring arm being secured to said reciprocatory element and the other end being connected to said circuit controller on one side of its axis and a second spring arm connected at one end to said element and bearing against said circuit controller on the other side ot its axis.

5. In an electric switch, a liquid contact circuit controller operable by rotation about its axis, a disk keyed to said circuit controller, an operating pin slidably mounted for reciprocatory movement, a flexible spring arm, one end of said spring arm being secured to said reciprocating pin and the other end being connected to said disk on one side of the axis of said circuit controller, and a second spring arm connected at one end to said element and bearing against said circuit controller on the other side of its axis.

6. In an electric switch, a base vof insulating material having spaced contact blades mounted thereon, a liquid contact circuit controller pivotally supported by said blades for rotation about its axis, a reciprocatory operating element, a member of insulating material keyed to said circuit controller, and a flexible spring arm fixed at one end to said operating element and being pivotally connected to said Ainsulating member at the other end for rotating said circuit controller upon movement of said element.

7. In an electric switch, a base of insulatingv material having spaced contact blades mounted thereon, a liquid contact circuit controller pivotally supported b y said blades for rotation about its axis, a reciprocatory operating element, a member keyed to said circuit controller, a exible spring arm, one end of said spring arm being se-l cured to` one end of said reciprocatory element and the other end being secured tov said member on one side of the axis of said circuit controller, and a second spring arm connected at one end to said reciprocatory element and bearing against said circuit controller on the other side of its axis.

8. An electric switch comprising longitudinally spaced bars, a base of insulating material supported at one end by said bars, transverse members supported between said bars at their other ends, spacedvcontact blades mounted on said base and disposed between said bars, a liquid contact circuit controller pivotally supported on said blades for rotation about its axis, an operating element slidably mounted in said transverse members for reciprocatory movement, a member keyed to said circuit controller, and a flexible bers supported between said bars at their other ends, spaced contact blades mounted on said base between said bars, a liquid contact circuit controller pivotally supported by said blades for roL tation about its axis, an operating element slidably mounted on said transverse elements for reciprocatory movement, a member keyed to said Acircuit controller, a flexible spring arm, one end of said spring arm being secured to said slidable element and the other end being connected to said insulating member on one side of the axis of said -circuit controller, and a second spring arm connected at one end to said slidable element and bearing against said circuit controller on the other side of its aids.

PHIIJP HUTI. 

